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As organoids and organ-on-chip (OoC) systems move toward preclinical and clinical applications, there is an increased need for method validation. Using a liquid chromatography-mass spectrometry (LC-MS)-based approach, we developed a method for measuring small-molecule drugs and metabolites in the cell medium directly sampled from liver organoids/OoC systems. The LC-MS setup was coupled to an automatic filtration and filter flush system with online solid-phase extraction (SPE), allowing for robust and automated sample cleanup/analysis. For the matrix, rich in, e.g., protein, salts, and amino acids, no preinjection sample preparation steps (protein precipitation, SPE, etc.) were necessary. The approach was demonstrated with tolbutamide and its liver metabolite, 4-hydroxytolbutamide (4HT). The method was validated for analysis of cell media of human stem cell-derived liver organoids cultured in static conditions and on a microfluidic platform according to Food and Drug Administration (FDA) guidelines with regards to selectivity, matrix effects, accuracy, precision, etc. The system allows for hundreds of injections without replacing chromatography hardware. In summary, drug/metabolite analysis of organoids/OoCs can be performed robustly with minimal sample preparation.

Organoids, i.e., laboratory-grown organ models developed from stem cells, are emerging tools for studying organ physiology, disease modeling, and drug development. On-line analysis of organoids with mass spectrometry would provide analytical versatility and automation. To achieve these features with robust hardware, we have loaded liquid chromatography column housings with induced pluripotent stem cell (iPSC) derived liver organoids and coupled the "organ-in-a-column" units on-line with liquid chromatography-mass spectrometry (LC-MS). Liver organoids were coloaded with glass beads to achieve an even distribution of organoids throughout the column while preventing clogging. The liver organoids were interrogated "on column" with heroin, followed by on-line monitoring of the drug's phase 1 metabolism. Enzymatic metabolism of heroin produced in the "organ-in-a-column" units was detected and monitored using a triple quadrupole MS instrument, serving as a proof-of-concept for on-line coupling of liver organoids and mass spectrometry. Taken together, the technology allows direct integration of liver organoids with LC-MS, allowing selective and automated tracking of drug metabolism over time.

Free-ranging wild ungulates are widespread in Austria, and act as hosts (i.e. feeding hosts) for ticks, including Ixodes ricinus, and as reservoir hosts for pathogens transmitted by I. ricinus. Due to climate change, the abundance of I. ricinus might be increasing, which could potentially lead to higher prevalences of tick-borne pathogens, such as Babesia spp. and Anaplasma phagocytophilum, some known for their zoonotic potential. Human babesiosis is classified as an emerging zoonosis, but sufficient data of these parasites in central Austria is lacking. In order to assess the abundance of vector-borne pathogens, blood of roe deer (Capreolus capreolus; n = 137), red deer (Cervus elaphus; n = 37), mouflons (Ovis gmelini; n = 2) and chamois (Rupicapra rupicapra; n = 1), was collected and tested for pathogen DNA in two different sampling sites in central Austria. DNA of tick-borne pathogens was detected in 15.5 % (n = 27) of these animals. Babesia capreoli (n = 22 in roe deer; n = 1 in mouflon), Babesia divergens (n = 1, in red deer), and Anaplasma phagocytophilum (n = 4, in roe deer) were detected. DNA sequencing of the 18S rRNA gene of two C. capreolus samples from Upper Austria featured another new genotype of Babesia, which differs in one nucleotide position to B. divergens and B. capreoli, and is intermediate between the main genotypes of B. capreoli and B. divergens within the partial gene sequence analyzed. This study thus confirms that B. capreoli, B. divergens, and A. phagocytophilum are present in free-ranging ungulates in central Austria. Further testing over a longer period is recommended in order to assess the impact of climate change on the prevalence of blood parasites in central Austria., (Copyright © 2021 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

Comparative (electro)catalytic, structural, and spectroscopic studies in hydrogen electro-oxidation, the (inverse) water-gas shift reaction, and methane conversion on two representative mixed ionic-electronic conducting perovskite-type materials La 0.6 Sr 0.4 FeO 3-δ (LSF) and SrTi 0.7 Fe 0.3 O 3-δ (STF) were performed with the aim of eventually correlating (electro)catalytic activity and associated structural changes and to highlight intrinsic reactivity characteristics as a function of the reduction state. Starting from a strongly prereduced (vacancy-rich) initial state, only (inverse) water-gas shift activity has been observed on both materials beyond ca. 450 °C but no catalytic methane reforming or methane decomposition reactivity up to 600 °C. In contrast, when starting from the fully oxidized state, total methane oxidation to CO 2 was observed on both materials. The catalytic performance of both perovskite-type oxides is thus strongly dependent on the degree/depth of reduction, on the associated reactivity of the remaining lattice oxygen, and on the reduction-induced oxygen vacancies. The latter are clearly more reactive toward water on LSF, and this higher reactivity is linked to the superior electrocatalytic performance of LSF in hydrogen oxidation. Combined electron microscopy, X-ray diffraction, and Raman measurements in turn also revealed altered surface and bulk structures and reactivities.

Purpose: Implant-associated osteomyelitis still represents a demanding challenge due to unfavourable biological conditions, bacterial properties and incremental resistance to antibiotic treatment. Therefore different bactericide or bacteriostatic implant coatings have been developed recently to control local intramedullary infections. Controlled local release of gentamicin base from a highly lipophilic gentamicin palmitate compound achieves extended intramedullary retention times and thus may improve its bactericide effect., Methods: Forty male Sprague-Dawley rats were divided into two groups receiving an intramedullary femoral injection of 10(2) colony-forming units (CFU) of a common methicillin susceptible Staphylococcus aureus strain (MSSA Rosenbach) and either an uncoated femur nail (Group I) or a nail coated with gentamicin palmitate (Group II). Animals were observed for 28 and 42 days. Serum haptoglobin and relative weight gain were assessed as well as rollover cultures of explanted femur nails and histological scores of periprosthetic infection in dissected femurs., Results: Implants coated with gentamicin palmitate significantly reduced periprosthetic bacterial growth as well as signs of systemic inflammation compared with uncoated implants., Conclusions: Gentamicin palmitate appears to be a viable coating for the prevention of implant-associated infections. These findings will have to be confirmed in larger animal models as well as in clinical trials.

Background: Impaired awareness of memory deficits has been recognized as a common phenomenon in Alzheimer's disease (AD) and research is now increasingly focusing on awareness in groups at risk for future dementia. This study aimed to determine whether levels of awareness differ among healthy elderly people and patients with subjective cognitive decline (SCD), amnestic and non-amnestic subtypes of mild cognitive impairment (aMCI, naMCI), Alzheimer's disease (AD) and Parkinson's disease (PD), to explore correlates of awareness and to establish frequencies of memory over- and underestimation within each diagnostic group., Methods: 756 consecutive outpatients of a memory clinic and 211 healthy controls underwent thorough neuropsychological testing. Impairment of awareness was measured as the difference between subjective memory appraisals (16-item questionnaire on current memory-related problems in everyday life) and objective memory performance (15-item delayed recall task). Subgroups of over- and underestimators were classified using percentile ranks of controls., Results: At group level, awareness significantly decreased along the naMCI→aMCI→AD continuum, with naMCI patients showing a tendency towards overestimation of memory dysfunction. PD patients showed accurate self-appraisals as long as memory function was largely unaffected. However, there was a considerable between-group overlap in awareness scores. Furthermore, different correlates of awareness were observed depending on the diagnostic group. In general, unawareness seems to be associated with decreased cognitive performance in various domains (especially memory), higher age and lower levels of depression and self-reported functional impairment., Conclusion: Impaired awareness is an important symptom in aMCI. Yet, given the considerable variability in awareness scores, longitudinal studies are required to evaluate their predictive power.

Abstract: A solid oxide electrolysis cell (SOEC) with a model-type La 0.6 Sr 0.4 FeO 3- δ thin-film cathode (working electrode) on an yttria-stabilized zirconia electrolyte and a porous La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3- δ counterelectrode was operated in wet argon gas at the cathode. The hydrogen formation rate in the cathode compartment was quantified by mass spectrometry. Determination of the current as well as outlet gas composition revealed the electrochemical reduction of some residual oxygen in the cathodic compartment. Quantitative correlation between gas composition changes and current flow was possible. At 640 °C a water-to-hydrogen conversion rate of ca. 4 % was found at -1.5 V versus a reversible counterelectrode in 1 % oxygen. Onset of hydrogen formation could already be detected at voltages as low as -0.3 V. This reflects a fundamental difference between steam electrolysis and electrolysis of liquid water: substantial hydrogen production in a SOEC is already possible at pressures much below ambient. This causes difficulties in determining the cathodic overpotential of such a cell.